Page 237 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

212 CHAPTER 1

VetBooks.ir Management for cosmetic reasons. In these horses, delicate exci-
sion is required to avoid penetrating the adjacent
Most horses are best not treated at all. Surgical
excision is indicated only if the lesion causes clini-
reported.
cal complications or if the owners insist on removal femorotibial joint capsule. Recurrence has not been

FEMUR

FRACTURES physeal fractures and are not readily apparent in acute
proximal fractures. Overriding of the fracture ends
Definition/overview shortens the distance between the greater trochanter
Femoral fractures may occur at any level of the bone. and the patella, resulting in an appearance of upward
Possible fracture locations include the head, neck and fixation of the patella and, generally, a shorter limb
greater trochanter, as well as fractures at the level of with a higher hock compared with the contralateral
the mid-diaphysis or the distal aspect of the femur. limb. Furthermore, the patella itself often feels loose
and can be manipulated sideways. Occasionally, a
Aetiology/pathophysiology major blood vessel, usually the femoral artery, may be
Femoral fractures are most commonly seen in very severed by the sharp fracture ends, resulting in clini-
young horses but can be found at any age. Fractures of cal signs of acute blood loss or fatal haemorrhage.
the femoral head and neck occur almost exclusively in
foals, usually after flipping over backwards or severely Differential diagnosis
abducting the hindlimbs. Similarly, other types of Coxofemoral luxation; upward fixation of the patella;
femoral fractures occur most commonly after an fractures of the patella or tibia; pelvis fractures;
external trauma such as a kick or a severe fall or, in muscle tear.
young foals, after being trodden on by their dam.
Femoral fractures in adult horses may also result from Diagnosis
a bad induction or recovery from general anaesthe- Presentation, clinical signs and findings on palpation
sia, although the tibia is more commonly involved. and manipulation of the limb are highly suggestive of
Diaphyseal fractures are commonly comminuted, a fracture, and auscultation with a stethoscope over
spiral or oblique in shape, and distal physeal fractures the femoral region may facilitate crepitus recogni-
are usually Salter–Harris type II with the metaphy- tion. Proximal physeal fractures are the most diffi-
seal component caudally. The extensive musculature cult to diagnose clinically. Rectal palpation of larger
surrounding the bone protects femoral fractures from animals may reveal the crepitation while the limb is
becoming open, and muscle contraction promotes manipulated. Soft-tissue swelling may be identified
significant overriding of the fracture ends. on the medial aspect of the thigh. For all fracture
types, radiography is required for definitive diagno-
Clinical presentation sis and determination of severity (Fig. 1.405). Due
Affected animals are non-weight-bearing lame, and to the musculature overlying the bone in an adult
crepitation and rotational instability are evident while horse, diagnostic images can usually be obtained
manipulating the limb. Haemorrhage and swelling in only for the distal aspect of the femur in a standing
the muscle may, however, keep the fracture ends sepa- position, although with the right equipment, oblique
rated, making it difficult to elicit crepitation. Young views of the coxofemoral joint can be obtained as
foals with a proximal physeal fracture can frequently well. All other cases require general anaesthesia
bear some weight on the affected limb. External rota- (Fig. 1.406), although in small foals, heavy seda-
tion of the limb, caused by the continuous pull of tion may suffice. If a displaced fracture is suspected,
the gluteal muscles, is common. Swelling and severe induction and recovery are likely to be difficult and
oedema are present in all diaphyseal and distal physeal general anaesthesia is therefore contraindicated.
fractures, may be mild in minimally displaced distal In these cases, ultrasonography may allow tracing